It is known that, in the domain of river weirs, gates are used in certain cases and particularly for surface works, which are adapted to regulate the flow or level of the water with a view to constituting movable weirs par excellence. Such a gate is an element presenting, in transverse section, the approximate shape of an aeroplane wing and which pivots longitudinally in order either to allow the water to pass when it is oriented horizontally, or to retain it when it is raised vertically or obliquely. The gates in question comprise a longitudinal sealing device fixed to the sill of the weir, of which the lip cooperates with the leading edge or face of the gate. On either side of the latter is provided a sealing device which ensures lateral tightness with the corresponding lock wall. Each sealing device comprises a lip disposed over the whole length of each lateral face of the gate and a rounded rib corresponding to the leading edge or face and which in fact extends it so as to abut by its lateral edge against the lock wall.
As the gates in question may attain very considerable lengths, of the order of 40 or 50 m, it goes without saying that the expansions or contractions that they undergo during temperature variations cause problems of tightness due to the contractions and problems of clamping of the two sealing devices against the lock walls, due to the expansions. During uses, such clamping provokes wear and tear of the rounded rib of each sealing device, so that leakages can be expected. The problem is, of course, not raised at the lip of the sealing device in question, since said lip is supple.
It is an object of the improvements according to the present invention to overcome these drawbacks and to provide a sealing device intended for the lateral tightness of a weir gate, whose efficiency is independent of the expansions or contractions thereof.